The convergence of the television receiver and the personal computer has accelerated with the advent of media center set-top computer systems. These systems, sometimes called set-top boxes, may use a conventional analog or digital television receiver as a display for computer systems. By combining the capabilities of a computer system and a television, the system may provide advanced television programming features, such as an electronic programming guide and time shifted viewing of broadcasted programs.
The set-top box may include personal video recorder (PVR) functionality. PVR is a generic term for a device that is similar to a video cassette recorder (VCR) but records television data in digital format as opposed to the VCR's analog format. A PVR allows a user to view a broadcasted program as a time shifted event. For example, the user may record a broadcasted program for later viewing, pause the broadcasted program and then resume watching the program at a convenient time for the user, replay a portion of the program, etc.
In a home environment, the set-top box may be set up to interface with multiple televisions using radio frequency remodulation (RF-remodulation). Here, the home cable is utilized by both the set-top box and the cable company. The cable company filters out certain frequencies to allow the cable subscriber to receive only the cable channels paid for by the subscriber. The set-top box takes the frequencies being filtered out by the cable company and puts a signal in those frequency spectrums. The set-top box transmits a NTSC signal to a television connected to coax cable or some other RF medium.
A user may view the same broadcasted program using two different scenerios. The first scenerio is when the user bypasses the set-top box and views the broadcasted program via cable only. For example, if the user is viewing the broadcasted program on cable channel 4, then the television must also be tuned to channel 4. Here, no time shifted functionality is available to the user.
In the second scenerio, the user may wish to view the broadcasted program on channel 4 with time shifted functionality. In this scenerio, the user needs to utilize the set-top box. But, if the set-top box is RF-remodulating on channel 101, for example, then the television must also be tuned to channel 101 for reception of cable channel 4. In the user's mind, he or she is viewing channel 4 even though the television is physically tuned to RF-remodulated channel 101.
In general, when the user turns the television off and returns later, the user expects the television to be automatically tuned to the last viewed channel (e.g., channel 4) once the television is turned back on. When channel 4 was last viewed via the first scenerio described above (e.g., directly on cable channel 4), the television automatically is tuned to channel 4 when it is turned back on. This is exactly what the user expects.
User confusion may present itself when channel 4 was last viewed by the user via the second scenerio described above (e.g., via set-top box and RF-remodulated channel 101) and the set-top box does not have a tuner available for the television when it is turned back on. Here, the set-top box must notify the user that no tuner is available for the television and that the television's remote control will not control the set-top box's tuner. Now, when the user presses channel down or channel up on the television's remote control, the channel is changed to either channel 100 or 102, respectively, and not channel 3 or 5 as the user anticipates. To avoid user confusion, the user must have a working knowledge of how the set-top box, the television and the remote control interact with each other. Unfortunately, many users do not have this working knowledge and don't care to learn.